Neopentasilane and methods of preparing the compound are known in the art. For example, Feher et al. (Inorg. Nucl. Chem. Lett. 1974, 10(7), 577-579) report the preparation of mixture of silanes, including neopentasilane, by acid decomposition of magnesium silicide and separation by distillation and gas chromatography.
Hoefler et al. (Inorg. Chem. Lett. 1973, 9(7), 723-725) report the hydrogenation of tetrakis(trichlorosilyl)silane with lithium aluminum hydride in diethyl ether at −100° C. to give a yellow-brown polymer which contained a 1:2 isotetrasilane-neopentasilane mixture.
Andrews et al. (J. Chem. Soc. A: Inorganic, Physical, Theoretical 1966, (1), 46-48) report the preparation of high molecular weight silicon-germanium hydrides using a silent electric discharge of 40 kV for 5-10 h in a conventional ozonizer tube maintained at −20° C. From the starting materials GeH4, SiH4, and Si2H6, the products isolated by gas-liquid chromatography included, among others, neopentasilane.
Although the aforementioned references describe the preparation of neopentasilane by various methods, including reduction of halosilanes, there remains a need for a method of preparing neopentasilane having high purity in high yield that is scaleable to a commercial manufacturing process.